Subaru Forester 2004 Service Manual page 111

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTIC)
Step
1 CHECK HARNESS BETWEEN ECM AND
FRONT OXYGEN (A/F) SENSOR CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM and
front oxygen (A/F) sensor connector.
3) Measure the resistance of harness between
ECM and front oxygen (A/F) sensor connector.
Connector & terminal
(B134) No. 26 — (B262) No. 3:
(B134) No. 33 — (B262) No. 4:
Check
Is the resistance less than 1
Ω?
EN(H4DOTC 2.5)-110
Yes
Replace the front Repair open circuit
oxygen (A/F) sen- in harness between
sor. <Ref. to ECM and front oxy-
FU(H4DOTC 2.5)- gen (A/F) sensor
36, Front Oxygen connector.
(A/F) Sensor.>
No